Purpose Following “AMO” framework and resource-based theory (RBT), the current study empirically examines the relationships between high-involvement human resource management (HI HRM) practices, employee functional flexibility (FF) and innovative work behavior (IWB). Furthermore, the mediating effect of FF has also been tested. Design/methodology/approach Descriptive statistics, correlation, hierarchical regression analysis, baron and Kenny, PROCESS Macro and Sobel Test approach were used on a sample of 894 employees of manufacturing concerns. Findings Findings revealed a direct effect of HI HRM practices on FF and IWB. In addition, the results confirm that FF positively mediates between HI HRM practices and IWB. Furthermore, three dimensions of HI HRM practices, i.e. ability-enhancing (AE), motivation-enhancing (ME) and opportunity-enhancing (OE) HRM practices also predicted FF and IWB. Practical implications This study not only offers the empirical evidence to validate the findings of past researchers, but also provide insight how HI HRM practices flourish the mechanism of FF in manufacturing concerns. Furthermore, this study highlighted some interesting facts that should be meaningful options for HR managers to enhance the level of employees' FF and IWB. Originality/value Although the empirical evidence is well established that HI HRM practices have a substantial contribution for organizational performance, however, there is lack of studies that empirically examine the associations among HI HRM practices, employee's competencies and behaviors, as well as the mechanism through which HI HRM practices affect work related innovative behavior. Finally, in distinguishing from the past studies, this study explores HI HRM practices as an important predictor of FF in addressing the IWB.